Shelf with integral front

ABSTRACT

In the preferred form, the inner sheet plastic door panel has formed in it an integral shelf and an integral shelf front in which the plastic sheet envelops a reinforcing bar above and parallel to the shelf.

O United States atent Inventor Keith K. Kesling Dayton, Ohio Appl. No.813,155

Filed Apr. 3, 1969 Div'sion of Ser. No. 684.049. Nov. 17, 1967, Pat. No.3.467 .741

Patented Aug. 10, 1971 Assignee General Motors Corporation Detroit,Mich.

SHELF WITH INTEGRAL FRONT lClaim,5Drawing Figs.

U.S.Cl 312/214, l8/35,2l1/l35,21l/153,312/l38 lnt.Cl A47f3/04,

[50] FieldofSeareh 211/153, 135; 312/138 A, 214; 264/92, 90; 18/35. 42,45

[56] References Cited UNITED STATES PATENTS 2,903,315 9/1959 Schoryetal. 312/214 3,401,996 9/1968 Rembold et al 312/214 FOREIGN PATENTS840,855 7/1960 Great Britain 312/214 Primary Examiner- Ramon S. BrittsAttorneys-William S. Pettigrew, Frederick M. Ritchie and Edward P.Barthel ABSTRACT: In the preferred form, the inner sheet plastic doorpanel has formed in it an integral shelf and an integral shelf front inwhich the plastic sheet envelops a reinforcing bar above and parallel tothe shelf.

PATENTEU AUG 1 019m K/ /)/V/ W f ilmlmlmlml w 7 m K ATTORNEY SHELF WITHINTEGRAL FRONT This application is a division of my copendingapplication Ser. No. 684,049, filed Nov. 17, 1967 now issued US. Pat.No. 3,462,741.

This invention relates to insulated doors having plastic sheet innerwalls provided with door shelves.

It is customary to make refrigerator doors with plastic inner walls.Shelves have been added in various ways such as are shown in theSaunders U.S. Pat. No. 2,837,816 issued June 10, 1958. It is notunusually difficult to provide integral shelves but the shelf frontshave been in the form of attached pieces.

It is an object of this invention to provide an integral shelf and shelffront upon the plastic inner wall of a door,

It is another object of this invention to provide an integral shelf andshelf front which contains a reinforcing bar enveloped in the plasticsheet forming the inner wall of the door. Further objects and advantagesof the present invention will be apparent from the followingdescription, reference being had to the accompanying drawings, wherein apreferred embodiment of the present invention is clearly shown.

IN THE DRAWINGS FIG. I is a vertical sectional view illustrating thefirst step in vacuum forming the inner wall of a door with integralshelves and shelf fronts embodying one form of my invention;

FIG. 2 is a vertical sectional view similar to FIG. 1 showing thecompletion of the vacuum forming process;

FIG. 3 is an enlarged sectional view showing the completed form oftheshelf front;

FIG. 4 is a fragmentary perspective view showing one of the integralcompleted shelves with an integral shelf front; and

' FIG. 5 is a vertical sectional view taken through the completed door.

Referring now to FIG. 1, there is shown a plastic sheet which is to beformed into the inner wall of an insulated door. The sheet 20 may be ofABS copolymer or polypropylene, for example. A vacuum forming door mold22 rests upon the support 24. This vacuum forming mold includes arelatively thick perimeter portion 26 which extends around a thin wallportion 28 provided with substantially uniform perforations 29. Theupper face of the mold 22 is provided with two shelf forming projections30 and 32 which extend between the wide portions 34, 36 of the sideperimeter 26. The portions 34 and 36 of the perimeter portions 26 whichextend to the left of the projections 30 and 32 are made of a width orheight equal to the height or protrusion of the shelf-formingprojections 30 and 32,

According to my invention, each of these portions 34 and 36 are providedwith notches 38 and 40 which receive and normally removably hold therectangular wooden sticks 42 and 44. The sheet 20 is clamped at itsedges between the turned down peripheral portion 46 of the rectangularholder 48 and an open rectangular member 50 which is clamped to theupper portion of the holder 48. The sheet-holding member 48 may beprovided with a plurality of infrared lamps 52 which are energized toheat the sheet 20 of plastic causing the plastic to be stretchable andformable. As the plastic 20 is heated, a valve 54 is opened to apply avacuum to the space or chamber 56 located between the support 24 and theperforated wall 28 of the mold 22. A pipe 58 forms a connection betweenthe valve 54 and the chamber 56. The valve 54 connects to a vacuum pipe60.

As the vacuum is drawn, the holder 48 is gradually lowered and the sheetof plastic is drawn into the large space between the shelves 30 and 32by the vacuum drawing air through the perforations 30, The plastic isheated and drawn by the differential in pressure thereon until theplastic sheet 20 envelops the shelf forming projections 30 and 32 and isalso completely around the sticks comprising the reinforcing members 42and 44 which form separate folds in upper flange portions in the plasticsheet 20. These sticks 42 and 44 are completely surrounded in theadjacent folds by the plastic sheet 20 and between each of the sticks 42and 44 and the adjacent shelf projections or lower flange portions 30and 32 the plastic sheet 20 comes into substantial flat contact shelffronts or webs 66. This forms a pleasing shelf front as is shown in FIG.4. The plastic also envelops both sides of the shelf forming projections30 and 32.

Before the completion of the vacuum-forming operation, the infraredlamps 52 are extinguished and the sheet plastic 20 forming the innerwall is removed from the mold 22 along with the sticks or reinforcingmembers 42 and 44 which are enveloped in the folds forming the shelffronts. The completed shelf structure is illustrated in FIG. 4. Thecompleted door is illustrated in FIG. 5 in which the inner wall isdesignated by the reference character 70.

The periphery of this inner wall member is fitted within a notchextending longitudinally in the bottom 72 of the magnetic door seal 74.The outer sheet metal wall 76 has a peripheral edge 78 provided with aninturned flange 80 extending within the interior and fitting against thebottom of the magnetic door seal 74 to hold it in place. The spacebetween the formed inner wall 70 and the outer wall 76 is preferablyfilled with polyurethane foam insulation 82 preferably containing aninsulating gas. This foam insulation fills the hollow space formed bythe shelf projections 30 and 32 to form the reinforced shelves 84 and86. The foam insulation adheres to the outer metal wall 76 and the innerplastic wall 70 and is rigid enough to substantially reinforce theshelves. These shelves are further reinforced by the integral shelffronts 66 immediately above wherein the two sheets of plastic aredirectly in contact. These shelves 84 and 86 are also reinforced by thereinforcing members 42 and 44 in the form of the sticks which areenveloped by the folds of the plastic sheet 20. By forming the shelffronts 66 by enveloping the reinforcing sticks 42 and 44 which areremovable from the mold 22, two integral shelf fronts are provided whichare formed each by a fold of the sheet of plastic 20, as an integralpart thereof. By this integral arrangement, the hollow shelf portions 84and 86 are reinforced by the shelf fronts 66 and'the reinforcing bars orsticks 42 and 44. The polyurethane foam 82 is relatively stiff andstrong even though it is of light weight. It has sufficient adhesivenessto prevent the separation of the inner and outer walls.

While the embodiment of the invention as herein disclosed constitutes apreferred form, it is to be under stood that other forms might beadopted.

I claim:

1. In combination, an insulated refrigerator door including an outermetallic wall extending generally within a plane, an inner wall formedof plastic sheet, polyurethane foam insulation material between saidinner and outer walls, said plastic sheet formed in cross section as aflanged beam by having an integral shelf portion extending substantiallyat right angles away from the adjacent portion of the sheet andsubstantially horizontally over an extensive area to a line extending inspaced relation to the adjacent portion of the sheet, wherein theimprovement comprises, said plastic sheet having a substantiallyhorizontal wooden reinforcing member of rectangular section extendingabove an extended portion of said shelf, said shelf portion of saidsheet formed with an integral rectangularly shaped loop portion foldedover and completely around said reinforcing member with opposite sidesof the fold in substantially flat contact over a substantial areabetween said reinforcing member and said shelf to form in cross sectionan upper flange portion of said flanged beam, said integral loop portionextending up along said line generally perpendicular to said extensivearea of said shelf portion to provide a front, said sheet extending fromsaid loop portion beneath the shelf portion to form an integral shelfand shelf front, said shelf portion being formed by the spacing of twoportions of said plastic sheet, and polyurethane foam insulation fillingthe space between said two portions to form in cross section a lowerflange portion ofsaid flanged beam.

1. In combination, an insulated refrigerator door including an outermetallic wall extending generally within a plane, an inner wall formedof plastic sheet, polyurethane foam insulation material between saidinner and outer walls, said plastic sheet formed in cross section as aflanged beam by having an integral shelf portion extending substantiallyat right angles away from the adjacent portion of the sheet andsubstantially horizontally over an extensive area to a line extending inspaced Relation to the adjacent portion of the sheet, wherein theimprovement comprises, said plastic sheet having a substantiallyhorizontal wooden reinforcing member of rectangular section extendingabove an extended portion of said shelf, said shelf portion of saidsheet formed with an integral rectangularly shaped loop portion foldedover and completely around said reinforcing member with opposite sidesof the fold in substantially flat contact over a substantial areabetween said reinforcing member and said shelf to form in cross sectionan upper flange portion of said flanged beam, said integral loop portionextending up along said line generally perpendicular to said extensivearea of said shelf portion to provide a front, said sheet extending fromsaid loop portion beneath the shelf portion to form an integral shelfand shelf front, said shelf portion being formed by the spacing of twoportions of said plastic sheet, and polyurethane foam insulation fillingthe space between said two portions to form in cross section a lowerflange portion of said flanged beam.